Anisotropic attenuation in rocks: Theory, modelling and lab measurements

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985530%3A_____%2F17%3A00473593" target="_blank" >RIV/67985530:_____/17:00473593 - isvavai.cz</a>

Alternative codes found

RIV/67985831:_____/17:00473593

Result on the web

<a href="http://dx.doi.org/10.1093/gji/ggw476" target="_blank" >http://dx.doi.org/10.1093/gji/ggw476</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1093/gji/ggw476" target="_blank" >10.1093/gji/ggw476</a>

Result language

angličtina

Original language name

Anisotropic attenuation in rocks: Theory, modelling and lab measurements

Original language description

Anisotropic attenuation affects seismic observations and complicates their interpretations. Its accurate determination is, however, difficult and needs extensive measurements of wavefields in many directions. So far, the traveltime and amplitude decay of waves are usually measured along a sparse grid of propagation directions, and methods for inverting for anisotropic attenuation are not fully developed. In this paper, we present theory allowing a description and parametrization of general triclinic anisotropic attenuation. We focus on a correct recalculation of ray quantities usually measured in lab to phase quantities needed in the inversion. We develop and numerically test an iterative inversion scheme for determining the parameters of anisotropic attenuation. We present a lab facility that allows for measuring anisotropic attenuation using the P-wave ultrasonic sounding of spherical samples in 132 directions distributed regularly over the sphere. The applicability of the proposed inversion method and the performance of the experimental setup are exemplified by determining triclinic anisotropic attenuation of the serpentinite rock from Val Malenco, Northern Italy. The ray velocity and ray attenuation were measured on a spherical sample of the rock with diameter of 45.5 mm at the room temperature and under two pressure levels: 0.1 and 20 MPa. The measurements confirmed that anisotropic attenuation is remarkably sensitive to confining pressure. Since cracks are closing with increasing pressure, attenuation decreases. However, changes in pressure can also induce changes in the directional variation of attenuation and rotation of anisotropy axes. The obtained results for the serpentinite rock sample are unique because they represent the first accurately determined triclinic anisotropic attenuation from lab measurements.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10507 - Volcanology

Project

Result was created during the realization of more than one project. More information in the Projects tab.

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year

2017

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Geophysical Journal International

ISSN

0956-540X

e-ISSN

—

Volume of the periodical

208

Issue of the periodical within the volume

3

Country of publishing house

GB - UNITED KINGDOM

Number of pages

16

Pages from-to

1724-1739

UT code for WoS article

000396818900033

EID of the result in the Scopus database

2-s2.0-85014385222